th400/np205 adapter

[blazin_blazer]

i've read there is a round & figure 8 bolt pattern. are they interchangable?
if not, which do i need to put a 2wd th400 short tailshaft trans in front of my '80 model 27 spline np205?
also where do i get a 32/27 spline coupler?
i was told to put the 2wd short th400 in place of my th350, all i have to do is remove tailshaft housing and use said parts....is this correct?
does the short tailshaft 2wd th400 have the right output shaft for this?

 

[blazin_blazer]

ok nobody knows?.... or everybody ignoring me b/c this has already been talked about at length?....link?

 

[goofy1]

I have only messed with the 4X4 version of the th400, but I think the tail section of the 2 wheel 400 is totally different. The 4X4 version has a 6-bolt round pattern of threaded holes(the bolts go through the adapter and screw into the back of the trans). look on e-bay for a np205 adapter and you will see some examples, if you look now you will see a 350 adapter it has a four bolt round pattern.

 

[blazin_blazer]

yes the th400 has a 6 bolt round pattern on it that holds the tailshaft housing on...the 4x4 th400 how long does the shaft stick out past the face that bolts to the adaptor, i was told that the 2wd th400 i have is same as 4x4 version after you remove the tailshaft housing...

 

[goofy1]

yes the th400 has a 6 bolt round pattern on it that holds the tailshaft housing on...the 4x4 th400 how long does the shaft stick out past the face that bolts to the adaptor, i was told that the 2wd th400 i have is same as 4x4 version after you remove the tailshaft housing...

Check this site out http://www.offroaddesign.com/NP205tech.htmthey know their stuff and were very helpfull to me over the phone(even tho I never bought anything from them, I was able to find my own for cheaper) when I swaped from 208-205

 

[nvrenuf]

There is no 27 to 32 spline adapter of any type.

You will need a short style 32 spline input for your 205 (this requires either a conversion bearing or boring the t-case body to fit the correct bearing).

You will also need a pre '85 OE 400/205 adapter (your current one will not work).

Some 2wd 400's have the correct tailshaft (I have used one for this same type of conversion). The only thing you can do is measure it, it shoud stick out of the back of the case approx 4.5". Check the ORD site to be sure on the measurement.

 

[1-tonmudder]

You will need a short style 32 spline input for your 205 (this requires either a conversion bearing or boring the t-case body to fit the correct bearing).

Does anybody have the part # for this bearing????

 

[blazin_blazer]

yes x2 on a conversion bearing.....i measured and indeed my shaft is indeed @4.5'' from housing face:-)...which requires the short 205 input..which is female, so no coupler is needed...that is neat....but i am still not sure of the difference between a figure 8 and round adapter or which i would need? ty guys

 

[goofy1]

yes x2 on a conversion bearing.....i measured and indeed my shaft is indeed @4.5'' from housing face:-)...which requires the short 205 input..which is female, so no coupler is needed...that is neat....but i am still not sure of the difference between a figure 8 and round adapter or which i would need? ty guys

I think the 80' model would have the fig 8 pattern. Look at the front of the case where it mounts to the adapter if the bolt holes are in a round pattern = round, if they are an oval =fig 8.

 

[nvrenuf]

Yep '80 = figure 8 or oval pattern.

up to '84 = figure 8 pattern (np205)

'85+ = round pattern (all t-cases)

 

[muddermilitia]

Yep '80 = figure 8 or oval pattern.

up to '84 = figure 8 pattern (np205)

'85+ = round pattern (all t-cases)

yup the 205 Im using for my doubler is an '85, long 32 spline input. You cant use that with a doubler and it has to be swapped for the short 32

 

[blazin_blazer]

so have u priced the input shaft, as i have to swap out my 27 spline. and is there really a conversion bearing, so i won't have to have the case machined, if so where can you get it?

 

[nvrenuf]

Yes, there is a bearing. Both Ratzila and Spicer have converted a 205 to 32 spline using a bearing that did not require machining the t-case. I don't have the part number but it's not hard to figure out. Go to an industrial bearing place (ie; Motion Industries, etc) and have them find a bearing with the correct dimensions -


Bearing with correct inner dia = "MRC 307 mg 5" (10/27 spline application)
Bearing with correct outer dia = "MRC 210 mg 2" (32 spline application)

Granted you will have to find someone willing to do the homework but that's how it was done on theirs.

 

[1-tonmudder]

Northwest fab will have the input for about $100 or so.

 

[muddermilitia]

Northwest fab will have the input for about $100 or so.

actually $125 to be exact. NWF is where I plan on getting all my t-case parts needed for the doubler/t-case rebuild